Friday, August 31, 2012

Above image shows Arctic sea ice extent (total area of at least 15% ice concentration) for the last 7 years, compared to the average 1972-2011, as calculated by the Polar View team at the University of Bremen, Germany.

Two earthquakes struck the waters off the coast of Jan Mayen Island on August 30, 2012. One had a magnitude of 6.8 on the Richter Scale and occurred at 13:43 pm (UTC), and was followed eight minutes later by a second one with a magnitude of 5.2 on the Richter Scale that took place on 13:51 pm (UTC).

The location of the earthquakes is indicated by the blue square on the top left of the USGS map below.

The Google map below shows that the location is on fault line extending north into the Arctic Ocean.

The map below shows the two earthquakes at the top in orange. The map shows all earthquakes with a magnitude 5.0 or higher that happened worldwide from August 1 to 30, 2012.

The largest earthquake in August 2012 was a magnitude 7.7 quake on August 14 in the Sea of Okhotsk, close to Sakhalin, Russia's largest island. With a depth of 626 km (389 miles), it was a "deep-focus" earthquake. Such quakes can be felt at great distance from their epicenters.

As the above map shows, this 7.7 M earthquake and the two recent ones off the coast of Jan Mayen Island occurred on the same fault line that goes over the Arctic. The danger is that further earthquakes on this fault line could destabilize methane hydrates in the Arctic, triggering release of huge amounts of methane.

The map below, from this page, shows fault lines and elevation in meters.

Wednesday, August 29, 2012

Arctic sea ice area was 13.70851 million square km on the 88th day of 2012, as illustrated on the image below by The Cryosphere Today. The image further below shows that only 2.59449 million square km was left of Arctic sea ice area on the 238th day of 2012. In other words, less than 19% is left of the sea ice area there was earlier this year.

Above diagram was part of a poster displayed at the 2011 AGU meeting in San Francisco by the Arctic Methane Emergency Group (AMEG). It was accompanied by the following text: In the Arctic, three problems are compounding one another: emissions causing global warming, sea ice loss causing accelerated warming, and methane releases further accelerating Arctic warming, with the danger of triggering runaway global warming.

The diagram pictures three kinds of warming and their main causes:

Emissions by people causing global warming, with temperatures rising around the globe, including the Arctic.

Soot, dust and volatile organic compounds settling down on snow and ice, causing albedo change. More heat is absorbed, rather than reflected as was previously the case. This causes accelerated warming in the Arctic.

Accelerated warming in the Arctic threatening to weaken methane stores in the Arctic with the danger that methane releases will trigger runaway global warming.

The diagram also pictures two feedback effects that make things even worse:

Methane feedback: Methane releases in the Arctic further add to the acceleration of warming in the Arctic, further contributing to weaken Arctic methane stores and increasing the danger that methane releases will trigger runaway global warming.

As described in various posts at this blog over time, there are further points that should be taken into account. Regarding sea ice loss, it's clear that where sea ice retreats, more open water appears, with the result that less sunlight is reflected back into space. Accelerated warming will also affect the integrity of the remaining sea ice, as well as of the snow and ice cover on land, including glaciers. This further adds to the albedo effect, causing less sunlight to be reflected back into space. Similarly, further feedbacks could be added or described in more detail.

Accordingly, ten feedbacks can be identified, and described as follows:

Albedo feedback: Accelerated warming in the Arctic speeds up the decline of ice and snow cover, further accelerating albedo change.

Methane feedback: Methane releases in the Arctic further add to the acceleration of warming in the Arctic, further contributing to weaken Arctic methane stores and increasing the danger that methane releases will trigger runaway global warming.

Currents feedback: Sea ice loss can cause vertical sea currents to weaken, reducing the cooling effect they had on the seabed. This can thus further cause sediments to warm up that can contain huge amounts of methane in the form of free gas and hydrates.

Storms feedback: Increased frequency and intensity of storms can cause substantially more vertical mixing of the sea water column, causing more warming of the seabed, thus further contributing to the warming of sediments, as above.

Storms feedback: Accelerated warming in the Arctic can result in more storms, causing mixing of cold Arctic air with warmer air from outside the Arctic. The net result is a warmer Arctic.

Storms feedback: More open waters can result in more storms that can push the ice across the Arctic Ocean, and possibly all the way out of the Arctic Ocean.

Storms feedback: Storms also cause more waves that break up the sea ice. Smaller pieces of ice melt quicker than large pieces. A large flat and solid layer of ice is also less susceptible to wind than many lighter and smaller pieces of ice that will stand out above the water and capture the wind like the sails of yachts.

Storms feedback: Storms cause waters to become more wavy. Calm waters can reflect much sunlight back into space, acting as a mirror, especially when the sun shines under a low angle. Wavy waters, on the other hand, absorb more sunlight.

Fires feedback: More extreme weather comes with heatwaves and storms. Thus, this is in part another storms feedback. The combination of storms and fires can be deadly. Heatwaves can spark fires that, when fueled up by storms, turn into firestorms affecting huge areas and causing huge amounts of emissions. Storms can whip up particles that when deposited on ice, snow or the bare soil, can cause more sunlight to be absorbed.

Open doors feedback: Accelerated warming in the Arctic causes the polar vortex and jet stream to weaken, causing more extreme weather and making it easier for warm air to enter the Arctic.

Snow and ice that grows in winter will act as a buffer when temperatures rise in summer. A bright snow and ice cover will reflect most sunlight back into space. Furthermore, a lot of the sunlight that isn't reflected will be consumed by the process of turning snow and ice into water, which occurs while temperatures remain at the melting point of 0°C (32°F, 273.15 K).

The Arctic is further protected from overheating by the polar vortex and jet stream, which act to keep cold air in the Arctic and keep warm air out. However, accelerated warming in the Arctic is now causing the polar vortex and jet stream to weaken. Accelerated warming in the Arctic alters the polar jet stream by slowing its speed and by increasing its waviness. Larger swings in the jet stream allow frigid air from the Arctic to plunge farther south, as well as warm, moist tropical air to penetrate northward, explains Jennifer Francis, research professor at the Institute of Marine and Coastal Sciences at Rutgers University.

The polar jet stream can travel at speeds greater than 100 mph. Here, the fastest winds are colored red;

What is described above can be regarded as an "open doors feedback". It's like leaving the doors open when it's cold inside and hot outside.

Accelerated warming in the Arctic comes with many such feedbacks, e.g. higher temperatures and more open water in the Arctic can also be expected to increase the danger that storms will batter the sea ice with greater ferocity. This is depicted in the image below.

In many ways, this is opening the doorways to doom. The biggest danger is that temperature rises will cause Arctic methane stores to weaken, resulting in huge amounts of methane to be released, triggering warming that could escalate into runaway global warming. The image below shows the sea surface temperature anomaly for August 27, 2012, by the National Oceanic and Atmospheric Administration (NOAA).

Rising temperatures in the Arctic threaten to trigger methane releases, as shown on the poster below.

Monday, August 27, 2012

Above image shows Arctic sea ice extent (total area of at least 15% ice concentration) for the last 7 years, compared to the average 1972-2011, as calculated by the Polar View team at the University of Bremen, Germany.

NSIDC scientist Walt Meier said, "By itself it's just a number, and occasionally records are going to get set. But in the context of what's happened in the last several years and throughout the satellite record, it's an indication that the Arctic sea ice cover is fundamentally changing."

According to NSIDC Director Mark Serreze, "The previous record, set in 2007, occurred because of near perfect summer weather for melting ice. Apart from one big storm in early August, weather patterns this year were unremarkable. The ice is so thin and weak now, it doesn't matter how the winds blow."

"The Arctic used to be dominated by multiyear ice, or ice that stayed around for several years," Meier said. "Now it's becoming more of a seasonal ice cover and large areas are now prone to melting out in summer."

With two to three weeks left in the melt season, NSIDC scientists anticipate that the minimum ice extent could fall even lower.

Saturday, August 25, 2012

Veli Albert Kallio in front of Peter Wadhams and John Nissen atAPPCCG event, March 13, 2012, House of Commons, London

I use three type sources to assess climate:

the peer-reviewed literature and news reports;

the whistle-blower organisations (Wikileaks, Cialeaks that release data files from the US Army, Navy, Air Force, CIA, the US State Department, or intercepted corporate telephone or Internet communications; and

indigenous people’s organisations and their ethnoclimatology people.

June 26, 2012: the Cialeaks released data files from the US stating that the North Pole will be ice free in 2013. These appear to be submarine upward sonar readings of ice from the US Navy. These contrast strongly what NSIDC is saying about the sea ice surviving much longer. I do not know the reason why US Navy and NSIDC advice differently on this point (an exponential trend projection based on PIOMAS data gives zero-ice 2015).

As per the question, where all heat goes after the sea ice has melted, I stick to the advice given in the United Nations General Assembly motion 101292: the Polar Ice responds extremely fast: first the sea ice melts and disintegrates, then followed by intense methane surges and equally rapid losses of the Arctic terrestrial ice cover in Greenland which never melts, but collapses instead.

After the sea ice loss, the permafrost and Greenland Ice Sheet take up a large portion of that energy that was previously used to melt the sea ice during the short summers. As a result, the ocean warms up and rains much more water than now with the flash-floods becoming very frequent in Greenland. As a result many times more water appears on top of Greenland’s Ice Sheet.

Greenland Ice Sheet rapidly metamorphoses from a (cold, dry, stable) moraine-forming ice sheet into a (warm, wet, dynamic) aggregate-forming ice sheet as the water amount within ice sheet and at its base increase. The bottom part of the ice sheet turns increasingly into water-logged, “mushy” ice that loses its internal strength, while pot holes on bedrocks become filled by water.

By 2020's 1/3 of Greenland Ice Sheet's base (between ice and bedrock) is dotted with water ponds at which point the rapid erosion processes (cavitation, plucking and kolking) pulverise the ice so aggressively that an "ice sheet thrust" develops against coastal perimeter at Melville Bay area. Even the dry parts of ice sheet then no longer can hold the ice dome in place and Heindrich Ice Berg Calving Event (H-1) occurs.

After the Heindrich Minus One (H-1) event the North Atlantic Ocean between America and Europe fills by broken ice that triggers a near-instantaneous severe climate cooling: the Last Dryas. Europe will see many years lasting freeze with Dryas Octopetala rapidly taking hold across continent's then barren soils. The ice volume is 10 times less in Greenland than in a similar event when the Hudson Bay Ice Dome reminders collapsed.

This ice evolution history of the First Nations of Americas as expressed on the UN General Assembly motion 101292 and the Plantagon Declarations, were used on the global-warming themed film “A Day After Tomorrow” and also “2012” by director Roland Emmerlich. Unfortunately, the films assigned incorrect physics and caused great annoyance among the Native American Indian communities due to many other inaccuracies in details therein:

“2012” films ‘mystery radiation of sun’ was never caused by neutrinos, but methane: the Bøllinger Years. The ‘core melting’ was due to the displacement of asthenosphere’s fluids as the heavy Foxe-Laurentide Ice Dome destabilised forcing the liquid minerals in asthenosphere to move out of way, the pressures causing huge eruptions and lava floods (asthenosphere is like a “wet sponge”, a composite of solid and liquid minerals).

“A Day After Tomorrow’s freeze failed the Boyle’s Law: ultra-cold stratosphere cannot fall, and cause instantaneous sea level jump that was followed by the Younger Dryas freeze-up, but ice can.

The First Nations of Americas have raised the alarm very clearly continuously for the last 20 years since the first Rio de Janeiro summit in 1992 that the West is living in delusions (including its scientists). Just like the perimeter between the south tip of the Baffin Island and the north tip of Newfoundland once failed, ending the Ice Ages, the rapid melt water accumulation same way destroys now Greenland’s perimeter barrier at Melville Bay. Wet solidus damage causing lava floods and inlet fjord leaks can suddenly speed it up even more unpredictably.

Here is Professor Oren Lyon Jr.’s (Native American Tradition-Keeper and Historian of the Six Nations who worked at the University of Buffalo), the Internet summary of the Plantagon Declarations: http://www.youtube.com/watch?v=4OjjPETcz6A

There is no point just to observe and repeat only points that appear in the professional literature. I want other communities’ perspectives and wisdom to be also realised and acknowledged:

+ either: the ancient experiences of the ancient people,

+ or: for the huge risks that people take to uncover often illegal practises by the corporations who are often acting in tacit co-operation with government officials, scientists or industrialists who are hostile to admit publically the role of greenhouse gases that violate their pet paradigm that the economic growth can be based on infinite growth from fossil-fuelled supply of goods and services.

Losses of 100,000 square kilometer per day loss of sea ice area are being reported by various sources. Images of ice speed and drift, in conjunction with ice thickness, would support this.

This rate of loss is as large as that lost during the August 3rd to 10th cyclone (700,000 to 800,000 square kilometers lost for the duration of the cyclone).

My prediction that we'll lose virtually all sea ice by September 30th, 2012, still seems very reasonable.

Sam Carana
I too estimate there have been losses of 100,000 square kilometer per day for over two months now.

The top image at my recent post on ice extent shows that extent has roughly halved in two months time, from over 12 million square km at the start of June to roughly 6 million square km at the start of August. That's a loss of about 6 million square km in two months time, or about 100,000 square km per day.

To date, this loss rate appears to have continued in August and shows no signs of decreasing yet.

Friday, August 24, 2012

The image below, edited from the National Snow & Ice Data Center (NSIDC), shows the situation according to the NSIDC updated at August 23, 2012. It's clear that Arctic sea ice extent looks set to reach the 2007 record low within days, if it hasn't been reached already now.

For updates, see the daily images produced by the NSIDC. Note that, to calculate extent, both the NSIDC and the Univeristy of Bremen include areas that show at least 15% sea ice. In the image below, from the Danish Meteorological Institute (DMI), areas with ice concentration higher than 30% are included to calculate ice extent.

Sunday, August 19, 2012

The increasing melt may be a harbinger of greater changes such as the release of methane compounds from frozen soils that could exacerbate warming, and a thaw of the Greenland ice sheet, which would contribute to rising sea levels, NASA’s top climate scientist, James Hansen, said in an e-mail interview, reports Bloomberg.

“Our greatest concern is that loss of Arctic sea ice creates a grave threat of passing two other tipping points -- the potential instability of the Greenland ice sheet and methane hydrates,” Hansen said. “These latter two tipping points would have consequences that are practically irreversible on time scales of relevance to humanity.”

Above image shows methane levels over a period of four years, from August 1, 2008, to August 1, 2012.

Above image shows methane levels over one years, from August 1, 2011, to August 1, 2012. This shows a marked increase in methane levels on the last of the four years further above.

Above image shows methane levels from August 1, 2012, to August 15, 2012. The image shows high levels of methane across the northern hemisphere. Note the high levels above Greenland.

Snow and ice protect the Arctic from overheating in summer. Firstly the brightness of the snow and ice cover ensures that most sunlight gets reflected back into space. Secondly, a lot of the sunlight that isn't reflected will be consumed by the process of turning snow and ice into water, which occurs while temperatures remain at the melting point of 0°C (32°F, 273.15 K). The Arctic is further protected from overheating by the polar jet stream, which keeps cold air in the Arctic and keeps warm air out.

Accelerated warming in the Arctic can alter the polar jet stream in a number of ways, firstly by slowing its speed and secondly by increasing its waviness. Larger swings in the jet stream allow frigid air from the Arctic to plunge farther south, as well as warm, moist tropical air to penetrate northward, explains Jennifer Francis, research professor at the Institute of Marine and Coastal Sciences at Rutgers University.

Accelerated warming in the Arctic comes with many feedbacks, and this "open doors feedback" is only one of them. Higher temperatures and more open water in the Arctic can also be expected to increase the danger that storms will batter the sea ice with greater ferocity.

In many ways, it's opening the doorways to doom. The biggest danger is that Arctic methane stores will weaken, causing huge amounts of methane to be released, triggering warming that could escalate into runaway global warming.

Thursday, August 16, 2012

The image below shows how much the older, thicker sea ice has declined over the years. This decline doesn't become apparent when focusing on sea ice extent; volume measurements are needed to reveal this decline.

Old versus new ice in Arctic: The maps show the median age of sea ice in March 1985 (left) and March 2011 (right).Overall, the proportion of old ice has decreased. By March 2011, ice over 4 years old accounts for less than10% of the Arctic ice cover. Credit: National Snow and Ice Data Center, University of Colorado, Boulder.

In a recent interview, Dr Laxon said that if the current trend continues, the Arctic could be ice-free at the height of summer by the end of the decade.

John Nissen, Chair of the Arctic Methane Emergency Group (AMEG), comments: "Dr Laxon failed to mention the data on sea ice thickness that has been collected over many years by sea ice expert Professor Peter Wadhams of the University of Cambridge, who now considers that the Arctic Ocean will be seasonally free of sea ice most probably by September 2016. PIOMAS sea ice volume data suggest that a collapse in sea ice area could occur even sooner, as discussed on the AMEG blog posting."

Tuesday, August 14, 2012

The National Snow and Ice Data Center (NSIDC) at the University of Colorado has released an update. Excerpts follow below, for the full post, see A summer storm in the Arctic.

Arctic sea ice extent during the first two weeks of August continued to track below 2007 record low daily ice extents. As of August 13, ice extent was already among the four lowest summer minimum extents in the satellite record, with about five weeks still remaining in the melt season.

Arctic sea ice extent as of August 13, 2012. Credit: National Snow and Ice Data Center

The average pace of ice loss since late June has been rapid at just over 100,000 square kilometers (38,000 square miles) per day. However, this pace nearly doubled for a few days in early August during a major Arctic cyclonic storm, discussed below.

Unlike the summer of 2007 when a persistent pattern of high pressure was present over the central Arctic Ocean and a pattern of low pressure was over the northern Eurasian coast, the summer of 2012 has been characterized by variable conditions. Air tempertures at the 925 hPa level (about 3000 feet above the ocean surface) of 1 to 3 degrees Celsius (1.8 to 5.4 degrees Fahrenheit) above the 1981 to 2012 average have been the rule from central Greenland, northern Canada, and Alaska northward into the central Arctic Ocean.

Cooler than average conditions (1 to 2 degrees Celsius or 1.8 to 3.6 degrees Fahrenheit) were observed in a small region of eastern Siberia extending into the East Siberian Sea, helping explain the persistence of low concentration ice in this region through early August.

August 6, 2012, 06:00 GMT surface weather analysis, showing a very strong cyclone over the central Arctic Ocean north of Alaska. The isobars (lines of equal pressure) are very tightly packed around the low pressure system, indicating strong winds. Greenland is on the right side of the figure, Canada at the bottom. Credit: Canadian Meteorological Centre

A low pressure system entered the Arctic Ocean from the eastern Siberian coast on August 4 and then strengthened rapidly over the central Arctic Ocean. On August 6 the central pressure of the cyclone reached 964 hPa, an extremely low value for this region. It persisted over the central Arctic Ocean over the next several days, and slowly dissipated. The storm initially brought warm and very windy conditions to the Chukchi and East Siberian seas (August 5), but low temperatures prevailed later.

On three consecutive days (August 7, 8, and 9), sea ice extent dropped by nearly 200,000 square kilometers (77,220 square miles). This could be due to mechanical break up of the ice and increased melting by strong winds and wave action during the storm.

The image below, from the Danish Meteorological Institute (DMI), shows that sea ice extent took a huge dive early August and has consolidated since, as the winds settled down.

Paul Beckwith fears that another Arctic cyclone could be starting up about 5 days from now.

GFSx model shows it churning from about August 19th or 20th onward to the end of the forecast (at least for 5 days+). It appears that this storm will be positioned closer to the Atlantic side, and be north of Greenland.

There will be a very high pressure mass of warm air over Greenland and the cyclonic flow will be pushing ice toward the Atlantic. Paul stands by his prediction of no sea ice in the Arctic by September 30th. There still is some 30 to 40+ days of melt season left. Paul adds that the 40+ days will more likely apply due to warmer water from storm churning.

The PIOMAS data for the annual minimum values are the black dots. The trend (in red) is added by Wipneus and points at 2015 as the year when ice volume will reach zero. Note that the red line points at the start of the year 2015. The minimum in September 2014 will be already be close to zero, with perhaps a few hundred cubic km remaining just north of Greenland and Canada.

Above image, again based on PIOMAS data, shows trends added by Wipneus for each month of the year. The black line shows that the average for the month September looks set to reach zero a few months into the year 2015, while the average for October (purple line) will reach zero before the start of the year 2016. Similarly, the average for August (red line) looks set to reach zero before the start of the year 2016.

In conclusion, it looks like there will be no sea ice from August 2015 through to October 2015, while a further three months look set to reach zero in 2017, 2018 and 2019 (respectively July, November and June). Before the start of the year 2020, in other words, there will be zero sea ice for the six months from June through to November.

Actually, events may unfold even more rapidly. As the ice gets thinner, it becomes more prone to break up if there are storms. At the same time, the frequency and intensity of storms looks set to increase as temperatures rise and as there will be more open water in the Arctic Ocean.

Above photo features Peter Wadhams, professor of Ocean Physics, and Head of the Polar Ocean Physics Group in the Department of Applied Mathematics and Theoretical Physics, University of Cambridge. Professor Wadhams has been measuring the sea ice in the Arctic for the 40 years, getting underneath the ice with the assistance of submarines, collecting ice thickness data and monitoring the thinning of the ice. This enabled 1970s data and 1980s data to be compared, which showed that the ice had thinned by about 15%. Satellite measurements only started in 1979.

Thinning of the ice is only one of the problems. "The next stage will be a collapse," Professor Wadhams warns, "where the winter growth is more than offset by the summer melt. If we look at the volume of ice that is present in the summer, the trend is so rapidly downwards that this collapse might happen within three or four years."

Apart from melting, strong winds can also influence sea ice extent, as happened in 2007 when much ice was driven across the Arctic Ocean by southerly winds. The fact that this occurred can only lead us to conclude that this could happen again. Natural variability offers no reason to rule out such a collapse, since natural variability works both ways, it could bring about such a collapse either earlier or later than models indicate.

In fact, the thinner the sea ice gets, the more likely an early collapse is to occur. It is accepted science that global warming will increase the intensity of extreme weather events, so more heavy winds and more intense storms can be expected to increasingly break up the remaining ice, both mechanically and by enhancing ocean heat transfer to the under-ice surface.

Sunday, August 12, 2012

The exponential increase in the Arctic atmospheric methane derived from the destabilization of the subsea Arctic methane hydrates is defined by both the exponential decrease in the volume of Arctic sea ice due to global warming and the exponential decrease in the continent wide reflectivity (albedo) of the Greenland ice cap caused by increasing rates of surface melting which reach minima around 2014, 2015.

The high anomalous atmospheric methane contents recorded this year at Barrow Point Alaska (up to 2500 ppb - Carana 2012b) and the fact that the surface atmospheric methane contents may be linked via a stable partial pressure gradient with increased maximum methane contents in the world encompassing global warming veil (estimated at ca 1460 ppb methane) makes it imperative that the Merlin lidar satellite be launched as soon as is feasibly possible. The Merlin lidar satellite will give us a clear idea of how high the Earth’s stratospheric methane concentrations are in this poorly documented giant methane reservoir formed above the ozone layer at 30 km to 50 km altitude (Ehret, 2010).

Methane detecting Lidar instruments could also be installed immediately on the International Space Station to give early warning of the methane buildup in the stratosphere and act as a back up in case the Merlin satellite fails.

Unless immediate and concerted action is taken by governments and oil companies to depressurize the Arctic subsea methane reserves by extracting the methane, liquefying it and selling it as a green house gas energy source, rising sea levels will breach the Thames Barrier by 2029 flooding London. The base of the Washington Monument (D.C.) will be inundated by 2031. Total global deglaciation will finally cause the sea level to rise up the lower 35% of the Washington Monument by 2051 (68.3 m or 224 feet above present sea level).

Saturday, August 11, 2012

The image below shows an unusually large and powerful cyclone that was churning over the Arctic in early August 2012. Two smaller systems merged on August 5 to form the storm, which at the time occupied much of the Beaufort-Chukchi Sea and Canadian Basin, reports NASA Earth Observatory. On average, Arctic cyclones last about 40 hours; as of August 9, 2012, this storm had lasted more than five days.

This cyclone’s central sea level pressure reached about 964 millibars on August 6, 2012—a number that puts it within the lowest 3% of all minimum daily sea level pressures recorded north of 70 degrees latitude, noted Stephen Vavrus, an atmospheric scientist based at the University of Wisconsin.

Many excellent comments were also added underneath these posts, e.g. by Steve Coulter who noted that "when fragmented floes are present, each irregular piece of ice acts as a sail in the wind, so the wind transfers momentum more readily to the surface. And each piece of ice, being 90% submerged, quite effectively transfers that momentum to the water. With winds moving in essentially a single direction in any given area, vast volumes of surface water are more readily put into motion. The difference in motion between the surface and deep water inevitably creates mixing."

Such mixing could mean that sediments that have been frozen until now get exposed to warmer water. This could destabilize methane contained in such sediments, either in the form of free gas or hydrates.

"There are at least three positive feedbacks working together to reinforce one another - and now a fourth on salinity:

The albedo flip effect as sea ice is replaced by open water absorbing more sunlight, warming and melting more sea ice.

As the sea ice gets very thin, it is liable to break up easily and get blown into open water where it will melt more easily.

The open warmer water is allowing increased strength of storms, which break up the ice to make for more open water.

The storms are churning up the sea to a depth of 500 metres, producing salinity at the surface that will mean slower ice formation in winter and more open water next year.

These feedbacks are dangerous for methane. AMEG has been warning that, as the sea ice retreats, storms will warm the sea bed, leading to further release of methane. In ESAS, we only need mixing to a depth of 50 metres - so a storm capable of mixing to 500 metres will really stir things up.

These feedbacks are also dangerous for food security, already damaged through climate extremes induced by Arctic warming, hence our piece in the Huffington Post.

The only way to head off catastrophe is to cool the Arctic, which must involve geoengineering as quickly as possible. We must try to remain positive and determined about this, despite the gloomy news."

Videos

Global temperatures are rising fast. In the Arctic, temperatures are rising even faster (interactive charts below and right). For 2010 and 2011, NASA recorded anomalies of over 2°C at higher latitudes (64N to 90N), with anomalies of over 3°C at latitudes 79N and 81N in 2010.

For November 2010, anomalies of 12.5°C were recorded at latitude 71N, longitude -79 (Baffin Island, Canada). At specific moments in time and at specific locations, anomalies can be even more striking. As an example, on January 6, 2011, temperature in Coral Harbour, located at the northwest corner of Hudson Bay in the province of Nunavut, Canada, was 30°C (54°F) above average.